A great many therapeutic agents have been proposed up to present for treating diseases such as cancer; however the therapeutic agents are all have a limit in effect as pointed out by researchers. Thus, it has been desired to develop therapeutic agents and therapies having higher effects. Recently, development of a therapy using a gene transporting carrier has advanced. For example, a transformed microorganism is proposed (see for example, Patent Document 1), which uses an anaerobic enterobacterium having a nature of being accumulated in a hypoxic solid tumor when it is systemically administered and the transformant thereof expresses a gene encoding a protein having an antitumor activity or a protein having an activity to convert an antitumor substance precursor to an antitumor substance, in a target diseased site. Further development of this is expected as a new technology for delivering a drug which inevitably produces a side effect when it is systemically administered, to a tumor site effectively in a high concentration.
In the meantime, a promoter, a DNA encoding a signal sequence, a DNA encoding a polypeptide or an expression cassette comprising cloning sites for inserting these DNAs (see, for example, Patent Document 2) is proposed.